Are Sling Planes Aerobatic?

Sling Aircraft focuses on delivering reliable and safe aircraft. Maybe you are also wondering, are Sling planes aerobatic?

Aerobatics can be defined as intentional maneuvers involving a rapid change in an aircraft's attitude such as spins, loops, and 360° rolls. That may be somewhat at odds with an aircraft dubbed by its manufacturer as the most practical, safe, and reliable aircraft in the world.

Most aircraft can perform some form of aerobatics. Sling planes are mainly marketed and built for quality, comfort, and safe leisure travel. However, based on published performance data they have some aerobatic potential too.

Aerobatic aircraft tend to have specific aerodynamic qualities and performance characteristics. Sling planes share some of these characteristics, but not all. This article explains why Sling planes, like most aircraft, should be able pull off some aerobatic moves under the control of experienced pilots.

In this article, we will look at what makes a successful aerobatic aircraft, the Federal Aviation Administration (FAA) regulations surrounding the classification of aerobatic aircraft, and compare aerobatic aircraft characteristics to those of Sling Aircraft.

‍What Are Aerobatics?

Before we explore the aerobatic capabilities of Sling planes, we should be clear about what is meant by aerobatics.

According to both the International Civil Aviation Organization (ICAO) and the FAA, aerobatics are intentionally piloted maneuvers that result in rapid variations in an aircraft’s attitude or speed.

In other words, aerobatics is a particular form of flight, where an aircraft's performance and attitudes change rapidly. This includes, spinning, looping, and rolling an aircraft through 360° by yawing, pitching, and rolling.

The FAA’s definition is laid out in Federal Aviation Regulation (FAR) 91.303.

Though FAA FAR 91.303 does define non-parachute limitations of 30° for pitching and 60° for banking in relation to the horizon (anything above these limits require parachutes to be worn by all occupants of the aircraft), it doesn’t expressly define the degrees where a maneuver is defined as “aerobatic”.

That being said, FAA FAR 91.303 does define several limitations on where aerobatic flight maneuvers cannot be performed, these include:

• Over congested areas of communities
• Over open large gatherings of people
• Within 4 nautical miles of Federal airways (measured from the centerline)
• Below an altitude of 1,500 ft (460 m)
• If flight visibility falls below 3 statute miles

In addition, aerobatics can only be performed in Class B, C, D, and E airspace, Class A airspace remains restricted.

Most aircraft can perform some form of aerobatics. A glider can perform aerobatics by a simple loop or roll, while a steep pitch upwards is an example of helicopter aerobatics.

Aerobatic maneuvers are frequent in agricultural aircraft, whereas they are very rare in large commercial aircraft. On the other hand, certain aircraft are designed specifically to perform aerobatic maneuvers.

Typical Aerobatic Maneuvers

• Loop - the nose of the aircraft is pitched up until the aircraft has completed 360° of rotation. The loop entrance speed needs to be significantly higher than the aircraft stall speed so that the aircraft’s speed does not drop below stall speed as speed reduces during the climb
• Roll – a simple 360° roll of the aircraft on its axis. Variations include snap rolls which are rolls performed very quickly, and slow rolls which are drawn-out rolls
• Barrel Roll - a full 360° roll following a spiral path through the air without loss of altitude
• Combined roll and loop to form specific figures in space such as a figure ‘8’ or a pattern such as a cloverleaf
• Stall - the aircraft speed is reduced so that lift is lost, usually in a near-vertical climb. The aircraft starts to fall, usually pitching nose down. As the airspeed increases, flight resumes

Obviously, to perform these maneuvers a pilot requires considerable skill and training.

What Are the Characteristics Of An Aerobatic Aircraft?

A key characteristic of all aerobatic aircraft is a low wing load i.e. the total weight of the aircraft per square foot of aircraft wing area is relatively low, perhaps in some specialized aerobatic aircraft, less than 10lb/ft2, which is significantly lower than that of a standard aircraft.

Wing loading is also a useful indicator of the stalling speed of an aircraft, as wings generate lift from the motion of air passing over the wing (where the air pressure above the wing is less than the air pressure below the wing).

Larger wings are able to move more air, so aircraft with low wing loadings (large wing areas relative to their weight) will thus have lower stalling speeds, allowing them to perform quicker and more agile turns as a result, enhancing aerobatic performance.

Important characteristics of aerobatic aircraft that assist agility and stability include the following:

• Standard aircraft tend to have wing cross-sections that are cambered i.e. curved on the top, and flat on the bottom, enhancing lift when the aircraft is ‘right-side up’. As true aerobatic aircraft often exhibit inverted flight it’s helpful to have wings with symmetrical cross-sections
• Wing shape is also a factor. Without going into the details of aerodynamics, tapered wings, as opposed to constant-chord wings, improve an aircraft’s snap roll performance
• Fixed landing gear - the mechanics required for retractable landing gear are heavy. Aerobatic aircraft need to minimize weight with light airframes that are not weighed down by cumbersome equipment
• Small ‘taildragger’ wheel at the rear of the aircraft in lieu of a heavier nosewheel
• Tail shape - aerobatic aircraft tend to have a tab-shaped tails

Other important characteristics of aerobatic aircraft are their powerful engines and impressive climb rates.

What Are The Sling Aircraft Models Currently Available?

Sling is currently selling five different models of aircraft

• Sling LSA (Light Sport Aircraft)
• Sling 2
• Sling 4
• Sling TSi
• Sling High Wing

Sling’s stated mission is to create reliable, safe, and practical aircraft whilst still delivering the same value for money pilots expect.

Each Sling plane has a niche market and its own characteristics and are fully described on Sling Aircraft’s official website. We’ll look at each of these aircraft in turn.

Sling 2

A two-seater light sports aircraft (LSA), the Sling 2 was designed by Sling to be the “perfect training aircraft” owing to its easy handling characteristics, comparatively low maintenance and operating costs. Introduced in 2009, the Sling LSA has already proven popular, selling well over 300 copies to date!

Sling 4

A four-seater aircraft derivative of the Sling 2, the Sling 4 was designed by Sling to be a lightweight and more practical four-seater.

The Sling 4 maintains the easy handling characteristics of its predecessor but unlike the Sling 2, is actively marketed as a low-cost getaway aircraft, owing to its longer range, ability to carry a family of four and their luggage.

Sling TSi

A development of the Sling 4, the Sling TSi is designed to be a more refined version of it with a longer range and faster cruising speed (thanks in large part to its more powerful engine and higher service ceiling) to make it a more practical getaway aircraft.

Sling High Wing

Perhaps unsurprisingly, the Sling High Wing, often known as simply the Sling HW, is a derivative of the Sling TSi. Unveiled in 2019 and first flown in December 2020, the Sling HW is noticeably different from its predecessors in the fact that it is a high wing aircraft.

With better ground visibility, cruise speed and range, Sling aims to market the aircraft as the backcountry alternative to its previous models. Presently still undergoing flight testing, Sling is expected to begin deliveries by the end of 2022.

Sling Aircraft Performance Metrics and Appearance

In the table below I provide some key Sling planes performance metrics and compare these to some well-known aerobatic aircraft types. If you are a cadet or experienced pilot you may be able to quickly see how well-suited Sling aircraft are to aerobatic flying by scanning through this data.

Perhaps not surprisingly given their target market, Sling does not publish the metrics that aerobatic aircraft are typically measured by, such as wing load. The Sling 4 wing load is thought to be 14.8lb/ft2.

As can be seen in the table below, Sling aircraft speeds are similar to the example aerobatic aircraft. However, aerobatic aircraft tend to have more powerful engines and more impressive climb rates compared to Sling planes. It’s likely that aerobatic aircraft also have slightly lower wing loadings than Sling planes.

If we consider the aerodynamic aspects of Sling planes, we see that they tend to have cambered cross-section wings with a more fixed-chord shape in plan form.

Wheels are fixed but without tail-wheels (apart from the Sling 2 where a taildragger is an option). Sling planes' tails are more V-shaped than tab-shaped.

Add to this the market niche of Sling planes, we can see that they are not marketed as aerobatic aircraft. The market seems to be more targeted at comfortable, private leisure travel aircraft. And, whoever heard of a four-seater aerobatic?

So, Are Sling Planes Aerobatic?

Sling planes are not marketed or designed as aerobatic aircraft. Sling’s target market seems to be owners seeking quality, safe, and cost-effective leisure travel in private aircraft.

Having said that, based on their performance characteristics it seems that a Sling pilot could have some fun in a Sling plane with some aerobatic maneuvers, as long as the FAA’s stringent rules and requirements are met.

So, yes Sling planes can perform certain aerobatic maneuvers, but you’re unlikely to witness a Sling plane pulling those crazy stunts you might see at an airshow!

And one final note of caution. Whilst aerobatic training is imperative, pilots who want to perform aerobatic maneuvers do not need special licenses or other certifications.

However, aircraft do need to be approved for aerobatics. Not all aircraft are designed to take the significant g-forces that are exerted during aerobatic maneuvers.